Government Assistance, Revenue Estimate

No definition available.

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Namespace Prefix:	ceg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of asset from government assistance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483507/832-10-50-3

+ Details

Name:	us-gaap_GovernmentAssistanceAmountCumulative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of liability from government assistance.

+ References

+ Details

Name:	us-gaap_GovernmentAssistanceLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of decrease in liability from government assistance.

+ References

+ Details

Name:	us-gaap_GovernmentAssistanceLiabilityDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Indicates line item in statement of financial position that includes liability from government assistance.

+ References

+ Details

Name:	us-gaap_GovernmentAssistanceLiabilityStatementOfFinancialPositionExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Name:	us-gaap_GovernmentAssistanceLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in income from government assistance, classified as operating.

+ References

+ Details

Name:	us-gaap_GovernmentAssistanceOperatingIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentAssetsMember
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Government Assistance (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
Government Assistance (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Government Assistance [Line Items]
Government Assistance, Liability, Statement of Financial Position [Extensible Enumeration]	Other noncurrent liabilities		Other noncurrent liabilities
Nuclear PTCs
Government Assistance [Line Items]
Estimate		$ 304
Estimated nuclear PTC receivable	$ 130
Estimated nuclear PTCs credits used	40		$ 150
Estimated refunds recognized	1,030		1,030
Government assistance, operating income, increase (decrease)	$ (110)	$ (69)
Nuclear PTCs \| Deferred Costs and Other Assets
Government Assistance [Line Items]
Estimated nuclear PTC receivable			185
Nuclear PTCs \| Other Current Assets
Government Assistance [Line Items]
Estimated nuclear PTC receivable			$ 95